using System.Numerics;
using Content.Server.Xenoarchaeology.Artifact.XAE.Components;
using Content.Shared.Mind.Components;
using Content.Shared.Mobs.Components;
using Content.Shared.Teleportation.Systems;
using Content.Shared.Xenoarchaeology.Artifact;
using Content.Shared.Xenoarchaeology.Artifact.XAE;
using Robust.Shared.Collections;
using Robust.Shared.Containers;
using Robust.Shared.Random;
using Robust.Shared.Timing;
using Content.Shared.Tiles; // Frontier

namespace Content.Server.Xenoarchaeology.Artifact.XAE;

/// <summary>
/// System for xeno artifact effect that creates temporary portal between places on station.
/// </summary>
public sealed class XAEPortalSystem : BaseXAESystem<XAEPortalComponent>
{
    [Dependency] private readonly IRobustRandom _random = default!;
    [Dependency] private readonly LinkedEntitySystem _link = default!;
    [Dependency] private readonly SharedTransformSystem _transform = default!;
    [Dependency] private readonly SharedContainerSystem _container = default!;
    [Dependency] private readonly IGameTiming _timing = default!;

    /// <inheritdoc />
    protected override void OnActivated(Entity<XAEPortalComponent> ent, ref XenoArtifactNodeActivatedEvent args)
    {
        if (!_timing.IsFirstTimePredicted)
            return;

        var entXform = Transform(ent); // Frontier
        var map = entXform.MapID; // Frontier: Transform(ent)<entXform
        var entPosition = _transform.GetMapCoordinates(ent, entXform).Position; // Frontier
        var validMinds = new ValueList<EntityUid>();
        var mindQuery = EntityQueryEnumerator<MindContainerComponent, MobStateComponent, TransformComponent, MetaDataComponent>();
        while (mindQuery.MoveNext(out var uid, out var mc, out _, out var xform, out var meta))
        {
            // check if the MindContainer has a Mind and if the entity is not in a container (this also auto excludes AI) and if they are on the same map
            if (mc.HasMind && !_container.IsEntityOrParentInContainer(uid, meta: meta, xform: xform) && xform.MapID == map)
            {
                // Frontier: ensure range check (don't teleport people from across the map or off of protected grids)
                if (TryComp(xform.GridUid, out ProtectedGridComponent? grid) && grid.PreventArtifactTriggers)
                    continue;

                if (Vector2.Distance(_transform.GetMapCoordinates(uid, xform).Position, entPosition) > ent.Comp.MaxRange)
                    continue;
                // End Frontier: ensure range check (don't teleport people from across the map or off of protected grids)

                validMinds.Add(uid);
            }
        }
        // this would only be 0 if there were a station full of AIs and no one else, in that case just stop this function
        if (validMinds.Count == 0)
            return;

        if(!TrySpawnNextTo(ent.Comp.PortalProto, args.Artifact, out var firstPortal))
            return;

        var target = _random.Pick(validMinds);
        if(!TrySpawnNextTo(ent.Comp.PortalProto, target, out var secondPortal))
            return;

        // Manual position swapping, because the portal that opens doesn't trigger a collision, and doesn't teleport targets the first time.
        _transform.SwapPositions(target, args.Artifact.Owner);

        _link.TryLink(firstPortal.Value, secondPortal.Value, true);
    }
}